-ethanol costs more than petrol to produce so the federal govt has set up subsidies and fuel excise consessions to encourage the production of ethanol(from crops) to be added to petrol (presumably to reduce oil emissions... but lets not forget that the PM has been a close personal friend of Mr Goeff cox, the head of the "sugar can to fuel" comittee/organisation).
-many car manufacturers accept that up to 10% of ethanol in petrol (known as E10) has no detrimental effects on vehicles but they have strongly opposed high concentrations because of the lack of testing under these circumstances.
-significant quantities of ethanol-petrol (E10) is available widely throughout australia but because of some tight ass petrol station workers who dillute the petrol with higher levels of ethanol to gain higher govt subsidies, car manufacturers air on the side of caution and disapprove of this higher concentration of fuel.
-there are no RELIABLE studies that show that ethanol made in australia from wheat or molasses produce less greenhouse gas emmissions compared to the petrol in which it would be replacing
-to produce enough ethanol to replace the petrol at ur pumps, HUGE amounts of land would have to be devoted purely to growing crops of high starch grains such as maize, so that they can be used in the fermentation process
-in newer cars a mix of 10-20% ethanol can be used without needing engine modifications (doesnt mean the engine life will be the same though)
-the south american country you were thinking about would have been Brazil im fairly sure. in the 70's and 80's they used to use 25%ethanol in there petrol before the brazilian govt realise that it wasnt economically viable to continue to grow thousands of hectares of maize and sugar (the climate wasnt too good for these crops either) and they stopped in the early 90's. i read somewhere that they are actually going to/have started it again, just with better planning this time
-ethanol burns at a much lower temp than petrol too, the flashpoint of octane is around the 200C mark whereas ethanol is around 160.... meaning its enthalpy would be less, hence less calorific value surely... i dont see why that would give better fuel economy?
thats about all i cant remember from chemistry... if this doesnt answer you question, u learned something today
